Drum sieve



hJan11Z,1940. A.KUFFERATH DRUM S IEVE 2 Sheets-Sheet 1 Filed March 50, 1937 pppppapp@ ggaxxpppp@ .3.. qpxssa ...2...

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March 12, 1940. A, KUFFERATH 2,193,006

DRUM SIEVE Filed March 30, 195'? 2 Sheets-Sheet 2 [pren for:

Patented Mar. 12, 1940 UNIT-En :PATE-NFI" oF-FICE r Antonius Kuierath, Mariaweiler, nearf Duren, l AGermany,fassignor to N eulneyer.& Dimond,-lnc.,

` New Yorky N. Y., ancorpora-tion of :NewYork "This invention `relates lto drum sieves" "offthe kind comprising a-'drum body-and `a``Wire"mesh njacket tted `overfsaidbody. `-'Suclnfdrum sieves are used-forvario'us purposes, for example, in -pa-` per making machinery, and they are known by different terms according tothe purposes for which they YVare 'employed. In 'theseand other drum 'sieves, the cylindrical jacket sieve hasto be" rrnly and: imrnovablyV connected tothey drum body, land; "asfv a result," difliculties arise/Whenthe sieve jacket has to be replaced by a fresh one ow-ing'to Wearzor'fother'reasons. V"Sinceit is'fde- 'sired'tliat the sieve""shall tightly engage the drum"body, the imountingand removal are lacfcom'paniediby great difficulties. For4 thisVv reason also;` a sieve can'only lbe employed in connection with the' drum body which it lits exactly.

According "to the invention, the jacket 'of a Adrum sieve consists vof' Wire"mesh, the circum-l ference of Which is alteredby stretchingin the longitudinal direction or by rotation around the "axis" `of thedrumfi'This *enables metal sieve jackets to Lloeemployed -whichmay be mounted and' removed very easily and yet are applied to the drum body tightly, Without creases or joints. The saving of time resulting" from the 'facility of Vmounting andV pullingoi the"jacketst is, `hovvever,not the only advantage resulting from 'the utilization of theinvention. Thereis `the=con siderable furtheradvantagefthat the manufacture Vof fthe jackets is simplified, vsincethe di- "ameter of the sieve `neeo'lnot correspondex'actly to` that ofthe drum-body. --Moreover, the jacket may-'still-be used after it has become-distended by use or repeatedvmoun-ting -and removal, 'so that the juseful 4life of 4the lsieve jacket is increased. The considerably reduced interruption of Work occasicnedibylthe renewalofa'vsieve-is -evenA further reduced-"toa'substantial extentin whereby the sieve jacket could be secured to 'its drum bodyas atight fit, but these arrangements utilized acrease or split/joint in thesieve jacket for the `purpose of tightly fitting it. The joint `or crease was ,unavoidableA In "contrast, the `jacket accordingto; theyinventionlis'ffreef off-lall #creases lor split vfiointsfiand isv Ivariable in vits clear diameter,-sin`ce #the variation @of Lthe diameter vis e1ected'by stretching or rotation. v c

1 Forexample, Where alsieve jacketwithfa-sewn for-'weldedfseamffor ay circular woven sieve jacket -"-5 Iisv-used-the endsfof this sieve-'may beA engaged in end discs and4` these Amay belrelatively'rotat'ed. `After suchv twisting, thosewires volthejacket flwhich f Were-previouslyparallel to` the -drum axis Will extend diagonally thereto. At the lsame @I0 'time the f circumference fof the sieve vis reduced. so that it becomes tightly appliedfto fthedrum lbody. Means for rotating-the :sieve lends Aand 'for subsequentlyxing theml-may-'be mounted lat'lone'eorboth ends of the drum orfof'the sieve "jacket, l y Alternatively, the clear fdiarneter. of the/jacket may be 'alteredgvthat is tto say,reduce`d,vdimin ished -or` decreased vto ysubstantially 'l that `of the outside diameter of the drum bodygbyemploy- 20 ing a sieve fabricthev extent. ofwhich is reduced, Whenllongitudnal pull iis :applied thereto,in` a Id-irection `at right angles .to the pull. Thesieve ydiameter Will'then be increased When'the .jacket f-is compressed, i. e., contracted or shortened. In this condition, ythe `A jacket may fbefeasily l and quicklymounted-and removed. After the mounting, theA sieve fdiameteris reduced bythe appli- A`cation of longitudinal .pull to such `an extent that lit-"becomes tightly applied .to the drum bodyiand "hugs theA periphery of the` `drum l body 'circumferfv entially.

f According fto" a `further featureof the invention; a sieve'f'jacketthe diameter 'of Which-,is in- "ereased or ireducedv-bythe application ofy pres- 'sure forfpullhmay-Icomprisef a Wire `mesh with wiresextendingat ani angle tothedirection of "movement In .-s'uchA ata'bricthe `ivvarp rand' weft Vthreads do "not extend inf a' direction parallelfand Vperpendi'cularito'the side edges of fthe' jacket, .as 340 in the known sievesor in'afsievejacket the di- Vrameter of Which is' tobe varied by rotation as `described,`but V'at 'an obliquelangle to both. The "anglefat which?` the wires crossione-'ano'ther is lvariedfwhen thefjacket is'extendedor compressed @5 longitudinally, '.wherebythel clear diameter: of the jacket is also Lvaried. Pullingc meansf aredisposed at f one-for both ends otfthe fdrumibody, lwherebyrlongitudinal pull! may abe exerted upon Vthe sieve. These means may comprise,:for exf ample, an end disc or annular ring :in .which the 'end of the sieve is engaged, said end disc lorA an- 'nular ring being extensibly attached to Vtheldrum body andi substantially coextensive 1in; diameter 'therewithzandvbeing `moved iawaydromtherdrum, M5

for example, by screws which take a point of support on the drum end. This has the effect of making the drum body, or a portion thereof, elongatable. In this manner an end pull may be exerted upon the sieve, to which it yields, the diameter being simultaneously reduced until the sieve becomes tightly applied.

In the accompanying drawings -various embodiments of the invention are illustrated by way of example.

In Figure 1, the sieve jacket comprises a fabric I the wires of which extend in a direction parallel and perpendicular to the axis of the drum 2.

In this arrangement, there is no possibility of Y applying the sieve jacket tightly to the drum body by rotation or longitudinal pull. In Fgure 3 two end discs 4 are provided. At the left hand end the end disc of the drum body is indicated at 6 and is shown in dotted lines. One or both of the end discs 4 may be rotated relatively to one another, whereby the wires, which originally extend in directions parallel and perpendicular to the axis of the Adrum (Figure 3), assume a slantin'g position after the rotation, as shown in Figure 4, and the diameter of the jacket is reduced. In order that the end discs 4 shall notl spring back into their original position, they are secured in position with reference to the drum end disc, for example, by being screwed thereto.

An example of the mounting of the sieve jacket on the end discs is shown in Figure 2. in connection with a sieve fabric, which undergoes contraction transversely to the longitudinal direction when pull is applied in that direction. The pulling means, shown only at the left hand end of the sieve jacket, comprises the fittingpdisc 4 with screw bolts 5. The pulling means, like the rotational tensioning means may, of course, be disposed at both ends of the sieve jacket. The screw bolts 5 are supported on the end face 6 of the drum body, and sieve 3 is pushed over the drum body in a direction from right to left. Its left hand end is then placed over the fitting disc 4 and is clamped fast thereon by a clamp ring 'I with the aid of the screw 8, these clamping means being shown by way of example. The sieve 3 is then pulled longitudinally with the aid of the screw bolts 5, until it is tightly applied. The screw bolts 5 may also be utilized Vfor subsequently tensioning the sieve on the drum body.

The foregoing examples are not intended to restrict the invention to drums with terminal trunnions, the invention being equally applicable to drums with open ends. Moreover, the term drum sieve is not intended to restrict the invention to drums wherein a tight jacket is employed for the sake of its sifting properties, since jackets of other kinds may also be mounted and fixed according to the invention.,

Figure 5 shows diagrammatically part of a paper making machine, which includes a dandy roll Ill which runs on the wire cloth Il. The wire cloth is maintained in stretched position by the guide rolls I2. Reference characters I3 are suction boxes, I4 are tube rolls and I5 is the take-up roller forthe nished paper web.

Figures4 6 Vand 7 show the application'of the invention to sieve drums running on rollers or rotating in a bearing I8. y

Figure 6 shows in section one end of an open end drum, showing the drum jacket 20 `comprising a wire fabric and secured to an endgring 2 I. The end of the ysievejacket is ,fixed by means of a clamping ring 22 connected to the end ring 2l by means of screws 23. The end piece of the drum body comprises a cylindrical member 24 with a wide flange 25. After the end of the sieve has been clamped fast between the rings ZI and 22, the distance between the ring 2I and the iiange 25 may be increased by means of the threaded spindles'26 engaging iin tapped? bores of the `flange 25, and thereby the sieve may be stretched. The spindles 26 are secured by means of a lock nut 2l. The drum body has rods or tubes 29 extending in a direction parallel to the axis of the drum, said tubes or rods being supported by stiifening rings 30 or the like.

Figure 7 shows the end of a sieve drum with bearing mounting I8 and an alternative tensioning device according to the invention. The end of the sieve jacket surrounds an end ring 32 having a tapered surface 33, over which a holder ring 34 is placed. The holder ring has a correspondingly tapered inner surface. The free end of the sieve jacket is placed between the two vtapered surfaces, the outermost edge of the jacket being enlarged, if desired, by beading, folding or casting out with lead, in such a way as to fill up the annular groove 35. By pull of the jacket 20 towards the vright and of the parts 33 and 34 to the left, the sieve fabric 2i) is clamped fast automatically. This method of fixing has the advantage that it maybe easily released at any time.

`By means'of an end disc 36 and a thread 3l on the shaft 23, an axial pull may be exerted upon the sieve 2U. For this purpose the surface 38 is formed, for example,'for the reception of a lever or Spanner, whereby the rotation of the end d isc 36 is facilitated. During this operation the parts 32 and 34 may be held fast, so that the sieve is not rotated, but merely stretched. However, the end of the sieve may also be rotated together with the end disc 36. The end disc may be fixed against movement in any desired position by means of the lock nut 4U.

I claim:

l. A device of the character described, comprising a drum body and a wire netting with changeable mesh formation, the wires of said netting extending in a direction neither parallel nor perpendicular to the axis of said drum body, said netting held loosely on said body, and means for changing the mesh formation of said wire netting by stretching said netting in a longitudinal direction thereby reducing its diameter and at the same time forcing said netting against the circumference of said drum body.

2. A device of the character described, comprising a drum body and a wire netting hugging ydirection whereby said netting is caused to hug the circumference of said drum.l

3. A drum sieveV for paper. making machines comprising an open, rotatable, cylindrical drum body, an annular ring extensibly attached to at leastone end of said-drum body and substantially coextensive in 4diameter therewith, a wiremesh cylinder mounted upon the periphery of `said drum body, the wires composing said cylin- :der extending in a direction neither parallel-nor u perpendicular to the side edges vof the cylinder, means for securing the enclof said wire-mesh cylinder to said annular ring, and means for adjusting the distance between said annularring and the end of said drum body whereby the length of said wire-mesh cylinder `may be increased, thereby causing its diameter to de-` said cylinder extending in a direction neither A parallel nor perpendicular to the side edges of the cylinder, means for attaching the ends of said wire-mesh cylinder to said framework, means for elongating said framework between such points of attachment thereby axially stretching said wire-mesh cylinder and thus decreasing its diameter to substantially that of the outside diameter of the cylindrical framework ,andV causing it to hug the periphery of said framework circumferentially, and means for se curing said wire-mesh cylinder to the non-elonl gatable portion of said framework.

5. A drum sieve for paper making machines comprising a shortenable, rotatable, open, tubular framework, a wire-mesh sleeve mounted tightly upon the periphery of said framework and secured at the ends of said framework, said sleeve having wires positioned atv an oblique angle to the ends thereof and crossing each other at an oblique angle, and means for shortening said framework thereby axially shortening said sleeve and accordingly increasing its diameter to facilitate its removal from said framework.

6. A drum sieve for paper making machines comprising a rotatable, open, tubular framework, a wire-mesh sleeve mounted `tightly upon the periphery Aof said framework and secured at the ends of said framework, said sleeve having wires positioned at an oblique angle to the ends thereof and crossing each other atan oblique angle, and means for disattaching said wire-l mesh sleeve from saidframework thereby permitting axial contraction of said sleeve anda consequent increase of its diameter to facilitate the removal of said `wirernesh sleeve from said framework. 4

7. A drum sieve for papenmaking'machines comprising an extensible, rotatable, open, tubu-` lar framework, a wire-mesh sleeve mounted upon the periphery of said framework withthe wires composing said sleeve at an oblique angle to its ends, means for attaching said sleeve to .saidv framework, and means for elongating said framework between such points of attachment thereby axially stretching said sleeve and providing a-tight circumferential t of the Wire-mesh sleeve upon the periphery of the framework.

8. The method of vmounting a `cylindrical sieve with deformable mesh to a drum body, comprising passing a loosely fitting sieve formed of two sets of helically disposed wiresY crossing veach other over the drum'body and fastening its end parts onto a drum body, thereafter changing the wire mesh formation by moving the end parts `longitudinally relative to each other, thereby substantially equally tensioning each set of the wires of the sieve netting relative to the other, thereby reducing the diameter of the sieve until its inner surfaceis tightly drawn against the circumference of the drum body.

ANTONIUS KUFFERATH. 

